Fans gathered to see Swedish metal band Opeth perform Monday night at a suburban nightclub in Minnesota feared the worst when they were told frontman Mikael Åkerfeldt has suffered "quite a serious accident" and wouldn't take the stage, the local Star Tribune newspaper reported.

Rumours began circulating in the crowd at the Myth nightclub in Maplewood that the 38-year-old Swedish singer and guitarist had been in a serious car wreck while on tour in the United States with fellow metal act Mastodon.

While Åkerfeldt had indeed been injured and rushed to hospital, the circumstances surrounding his wound turned out to be somewhat less dramatic, if not more bizarre, than originally feared.

"All that happened is I hit my head in Mastodon's [sic] tour bus as I was getting a new pair of (red) underwear out from my suitcase," Åkerfeldt wrote in a statement on the band's website following the incident.

He explained that the unintended head-banging left him with a gash "open down to the skullbone" which required eight metal staples to repair.